The study on the rheological properties of two types of wood ear extracted polysaccharides and the effect of their interaction with rice starch
| Autor: | Cheng-Fu Huang, 黃丞甫 |
|---|---|
| Rok vydání: | 2005 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 93 Two kinds of wood ear extracted polysaccharides called AP and TF ( extracted by Auricularia polytricha and Tremella fuciformis ) were detected those molecular weight by High Performance size exclusion chromatography ( HPSEC ), before the effects of different temperature, pH, sugar ( sucrose, trehalose and maltose ) and ionic strength ( NaCl, KCl and MgCl2 ) on the rheological properties of AP and TF solutions at dilute and semi-dilute states were investigated, using a capillary viscometer and dynamic rheometer with flow or small-amplitude oscillation mode. Basically, the intrinsic viscosity of the TF examined in aqueous solution was higher than that of the AP. The tendency of decreasing intrinsic viscosity by adding sugar and raising of ionic strength on AP solution was more notable. Dynamic rheometric examination showed that shear thinning occur on both AP and TF solution, and those solution did not undergo gelation, also the different pH did not result in difference. The tendency of decreasing storage modulus ( G' ) by raising temperature and increasing ionic strength on both AP and TF solution was detected, the effect of raising storage modulus on AP solution by adding sugar was significant, and trehalose can cause the most variation of storage modulus on TF solution. High concentration of trehalose and MgCl2 can cause the most variation of activation energies of deformation on both AT and TF solution. Rice starch from three cultivars ( TCN1, TNu67 and TCSW1 ) and two kinds of wood ear extracted polysaccharides were used as sample, investigate the influence of starch and polysaccharide intentioned on the starch-wood ear extracted polysaccharide mixtures by rapid visco analyser. The results show that the addition of both AP and TF can increase the viscosity of starch paste during heating process. Moreover, the effect extent was less than adding locust bean gum ( LBG ) . |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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